The crusades were a series of military expeditions by western European Christians to the Middle East in the twelfth and thirteenth centuries. The crusaders saw themselves as trying to free the Holy Land from the rule of the Muslims. The crusades were mainly directed toward Jerusalem and the Christian shrine of the Holy Sepulcher. There were eight major crusades.
The cause of the crusades is an issue of debate. It is widely believed that the crusades were purely holy wars, but many other motivating factors were actually involved. The crusades arose out of the feudal society of the eleventh century, and they offered crusaders freedom, adventure, and the possibility of economic gain. Also, the crusades were a defensive act against the flourishing Muslim state, which Christians perceived as a threat to their faith and their way of life.
The first crusade started when the Byzantine Emperor, Alexis Comnenus, requested aid from the west against the Muslims. Instead of just sending troops, Pope Urban II invited his people to engage in a holy war to take back Jerusalem. Peter the Hermit, a monk and priest, also began preaching the crusade (he even led an army during the first crusade that was defeated by the Turks). As a result, Alexis received crusaders in answer to his request, and the first crusade was born in 1095.
The volunteer crusaders faced an imposing task: crossing thousands of miles of unfamiliar territory to fight against unknown countries. Yet because of their great fervor, the crusaders managed to take Antioch in 1098. The crusaders took Jerusalem in 1099, killing 10,000 Jews and Muslims. The crusaders set up the Crusader States along the coast of Palestine and built up the cities they had conquered.
The third Crusade (1189-1192) was a response to the capture of Jerusalem. In 1187 Saladin, a great Muslim warrior and founder of the Ayyubid dynasty in Egypt, had recaptured Jerusalem. Unlike his Christian opponents, Saladin did not sack the city upon his victory. This Crusade was led by Frederick Barbarosa, the Holy Roman Emperor, King Richard I of England and King Philip II of France, three of Europe's most powerful monarchs. It accomplished little.
Over the next hundred years, many more crusades were launched, but the crusaders never again experienced great success. They ruled small areas of the coast until their final defeat by the Mamluks at Acre at the end of the thirteenth century. Overall, the crusades were a military failure. To the Arabs, they were just one more annoying barbarian invasion, not nearly as much of a threat as the Mongols were later.
Although many people were killed during the crusades, there were many positive results for both the east and the west. The most obvious result of the crusades was the establishment of trade routes between east and west, which in turn resulted in positive contact between the cultures. Although the pope initially tried to ban trade with the Muslims, he backed down in 1344, and a flourishing trade market was born that benefited the economy of both cultures. The combination of these cultures resulted in the invention of the windmill, the compass, gunpowder, and clocks. Scholarly exchange took place. For example, Muslim architects began to imitate the European pointed arch, while Europeans learned Greek medicine from the Muslims. Muslims and Europeans learned new military techniques from one another. As a result of learning new military strategies and uniting themselves against one cause, the Muslims developed a stronger religious nation. The crusades also accelerated the decline of feudalism and the Byzantine empire.
Sources:
Collier's Encyclopedia, (New York, P.F. Collier Inc., 1993)
Dictionary of the Middle Ages, Ed. Joseph R. Srayer (New York; Charles Scribner's Sons, 1984) Vol. 4
Islam and Islamic History in Arabia and the Middle East: The Crusaders
The Christian Crusades Positively Impacted the East and the West
The Crusades
The Crusades: A Defensive Gesture
The Encyclopedia Americana International Edition (Grolier Inc., 1988)
The New Encyclopedia Britannica, (Chicago, Encyclopedia Britannica Inc., 1992) Vol. 3